U.S. patent number 6,108,859 [Application Number 09/124,324] was granted by the patent office on 2000-08-29 for high efficiency squeegee.
This patent grant is currently assigned to Alto U. S. Inc.. Invention is credited to Jack L. Burgoon.
United States Patent |
6,108,859 |
Burgoon |
August 29, 2000 |
High efficiency squeegee
Abstract
A squeegee for use with a mobile surface scrubber to collect
used liquid on a surface after being cleaned by the scrubber. The
scrubber includes a mobile frame, a cleaning solution dispensing
system mounted on the frame for wetting the surface with liquid,
and at least one scrub brush attached to the frame for scrubbing
the surface when wetted with liquid. In addition, the scrubber
includes a vacuum system connected to the frame for removing liquid
from the surface. The squeegee includes an elongate squeegee blade
of flexible material having a lower edge engageable with the
surface to collect the liquid on the surface for removal by the
vacuum system. The squeegee also includes a series of openings
through the squeegee blade extending up from the lower edge at
intervals along the blade. Each opening tapers when the lower edge
engages the surface to provide a relatively wide gap at the lower
edge of the blade thereby permitting liquid to pass readily
therethrough, and a narrower gap at an upper end of the opening
having substantially no width thereby limiting passage of ambient
air through the opening.
Inventors: |
Burgoon; Jack L. (Toledo,
OH) |
Assignee: |
Alto U. S. Inc. (Chesterfield,
MO)
|
Family
ID: |
22414200 |
Appl.
No.: |
09/124,324 |
Filed: |
July 29, 1998 |
Current U.S.
Class: |
15/320; 15/340.4;
15/401 |
Current CPC
Class: |
A47L
11/30 (20130101); A47L 11/4038 (20130101); A47L
11/408 (20130101); A47L 11/4061 (20130101); A47L
11/4072 (20130101); A47L 11/4044 (20130101) |
Current International
Class: |
A47L
11/30 (20060101); A47L 11/29 (20060101); A47L
011/30 () |
Field of
Search: |
;15/320,340.4,401 |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
Clarke-American brochure entitled "Test Drive One of the Tough Ones
Clarke American: Autoscrubbers"; published prior to Jul. 29, 1998;
4 pages..
|
Primary Examiner: Till; Terrence R.
Assistant Examiner: Snider; Theresa T.
Attorney, Agent or Firm: Senniger, Powers, Leavitt &
Roedel
Claims
What is claimed is:
1. A squeegee for use with a mobile surface scrubber to collect
liquid on a surface after being cleaned by the scrubber, said
scrubber comprising a mobile frame, a cleaning solution dispensing
system mounted on the frame for wetting the surface with liquid, at
least one scrub brush attached to the frame for scrubbing the
surface when wetted with liquid, and a vacuum system connected to
the frame for removing used liquid from the surface, said squeegee
comprising:
an elongate squeegee blade of flexible material having a lower edge
engageable with said surface to collect liquid on the surface for
removal by the vacuum system; and
a series of openings through the squeegee blade extending up from
its lower edge at intervals along the blade, each opening tapering
when the lower edge engages the surface to provide a relatively
wide gap at the lower edge of the blade thereby permitting liquid
to pass readily therethrough, and a narrower gap at an upper end of
the opening having substantially no width thereby limiting passage
of ambient air through the opening.
2. A squeegee as set forth in claim 1 wherein the openings in said
squeegee blade are formed by slits in the blade, and wherein the
blade is adapted to deflect as it engages the surface to open the
slits thereby forming said relatively wide gaps at the lower edge
of the blade.
3. A squeegee as set forth in claim 2 wherein each opening tapers
substantially uniformly from said lower edge of the blade up to
said upper end of the opening.
4. A squeegee as set forth in claim 3 wherein each slit is defined
by a cut having a kerf of substantially no width.
5. A squeegee as set forth in claim 4 wherein the blade has an
upper edge opposite said lower edge and the squeegee further
comprises a series of slits through the squeegee blade extending
down from the upper edge at intervals along the blade so the blade
is invertible.
6. A squeegee assembly for use with a mobile surface scrubber to
collect liquid on a surface after being cleaned by the scrubber,
said scrubber comprising a mobile frame, a cleaning solution
dispensing system mounted on the frame for wetting the surface with
liquid, at least one scrub brush attached to the frame for
scrubbing the surface when wetted with liquid, and a vacuum system
connected to the frame for removing liquid from the surface, said
squeegee assembly comprising:
leading and trailing elongate squeegee blades of flexible material,
each blade having a lower edge engageable with said surface to
collect liquid on the surface for removal by the vacuum system;
a mount for mounting the leading and trailing squeegee blades to
the scrubber frame in spaced apart relation to define a chamber
therebetween for accumulating liquid collected by the squeegee
blades, the chamber communicating with the vacuum system for
removing accumulated liquid from the chamber; and
a series of openings through the leading squeegee blade extending
up from its lower edge at intervals along the blade, each opening
tapering when the lower edge engages the surface to provide a
relatively wide gap at the lower edge of the blade thereby
permitting liquid to pass readily therethrough into said chamber,
and a narrower gap at an upper end of the opening having
substantially no width thereby limiting passage of ambient air into
said chamber.
7. A squeegee assembly as set forth in claim 6 wherein the openings
in said leading squeegee blade are formed by slits in the blade,
and wherein the leading blade is mounted so as to permit the blade
to deflect as it engages the surface to open the slits thereby
forming said relatively wide gaps at the lower edge of the
blade.
8. A squeegee assembly as set forth in claim 7 wherein each opening
tapers substantially uniformly from said lower edge of the leading
blade up to said upper end of the opening.
9. A squeegee assembly as set forth in claim 8 wherein each slit is
defined by a cut having a kerf of substantially no width.
10. A squeegee assembly as set forth in claim 9 wherein said mount
comprises an arcuate blade support extending generally transversely
with respect to the scrubber, the support holding the blade so as
to permit the blade to deflect to conform to the surface.
11. A mobile surface scrubber for cleaning a surface with liquid,
said scrubber comprising:
a mobile frame;
a cleaning solution dispensing system mounted on the frame for
wetting the surface with liquid;
at least one scrub brush attached to the frame for scrubbing the
surface when wetted with liquid;
a vacuum system connected to the frame for removing liquid from the
surface;
leading and trailing elongate squeegee blades of flexible material
mounted on the frame, each blade having a lower edge engageable
with said surface to collect liquid on the surface for removal by
the vacuum system, the leading and trailing squeegee blades being
mounted on the frame in spaced apart relation to define a chamber
therebetween for accumulating liquid collected by the squeegee
blades, the chamber communicating with the vacuum system for
removing accumulated liquid from the chamber; and
a series of openings through the leading squeegee blade extending
up from the lower edge at intervals along the blade, each opening
tapering when the lower edge engages the surface to provide a
relatively wide gap at the lower edge of the blade thereby
permitting liquid to pass readily therethrough into said chamber,
and a narrower gap at an upper end of the opening having
substantially no width thereby limiting passage of ambient air into
said chamber.
12. A scrubber as set forth in claim 11 further comprising a mount
for mounting the leading and trailing squeegee blades to the
scrubber frame.
13. A scrubber as set forth in claim 12 wherein said mount
comprises an arcuate blade support extending generally transversely
with respect to the
scrubber, the support holding the blade so as to permit the blade
to deflect to conform to the surface.
Description
BACKGROUND OF THE INVENTION
This invention relates generally to a mobile surface scrubber for
scrubbing a surface wetted with cleaning solution, and more
particularly to a high efficiency squeegee system for collecting
liquid on the wetted surface.
Mobile surface scrubbers typically include a system for dispensing
cleaning solution on the surface to be cleaned, scrub brushes for
scrubbing the wetted surface and one or more squeegees for
collecting used solution on the surface. A vacuum system is usually
connected to the squeegee for removing the cleaning solution from
the surface once collected. In addition, scrubbers frequently
include sweeper brushes to sweep loose debris from the surface into
an on-board recovery bin before the surface is wetted. The
scrubbers may be used to concurrently sweep, scrub and squeegee the
surface, or they may be used to perform only one or two of these
functions at a time.
Conventional scrubber squeegees are arcuate so they direct liquid
toward their center as they move across the surface. In order to
improve the removal of liquid, conventional scrubber squeegees have
two blades mounted in spaced apart relation so they form a curved
chamber between them. As the scrubber moves across the surface,
liquid passes under the leading blade and accumulates in the
chamber. A vacuum system communicates with the chamber through a
port located above the center of the chamber to draw the
accumulated liquid into a holding tank and remove it from the
surface.
One or more openings are provided in or beneath the leading
squeegee blade to permit liquid to flow into the chamber between
the blades. For instance, sometimes the leading blade is mounted so
its lower edge is spaced above the surface to permit liquid to pass
beneath the blade. In other instances, the leading blade has either
slits or slots extending through it. Usually these openings extend
up from the lower edge of the blade at intervals along the blade.
Each opening has parallel sides spaced by a gap to permit liquid to
flow past the blade as it wipes the surface. The gaps provided by
the slits are narrow and thus do not allow an appreciable amount of
liquid to flow into the chamber. The slots provide wider gaps and
permit more liquid to flow past the leading blade into the chamber.
However, the wider slots also allow a relatively large amount of
ambient air to pass into the chamber. As larger amounts of air are
allowed into the chamber, the flow rate required to be produced by
the vacuum system to draw liquid out of the chamber increases.
Further, the power requirements of the motor used in the vacuum
system increase as the flow rate requirements increase.
SUMMARY OF THE INVENTION
Among the several objects and features of the present invention may
be noted the provision of a squeegee blade which permits liquid to
pass readily therethrough while limiting passage of ambient air;
the provision of a squeegee which is economical to manufacture and
use; and the provision of a squeegee which reduces the power
required to remove liquid from a surface with an associated vacuum
system.
Briefly, this invention is directed to a squeegee for use with a
mobile surface scrubber to collect liquid on a surface after being
cleaned by the scrubber. The scrubber comprises a mobile frame, a
cleaning solution dispensing system mounted on the frame for
wetting the surface with liquid, and at least one scrub brush
attached to the frame for scrubbing the surface when wetted with
liquid. In addition, the scrubber includes a vacuum system
connected to the frame for removing liquid from the surface. The
squeegee comprises an elongate squeegee blade of flexible material
having a lower edge engageable with the surface to collect the
liquid on the surface for removal by the vacuum system. The
squeegee also includes a series of openings through the squeegee
blade extending up from the lower edge at intervals along the
blade. Each opening tapers when the lower edge engages the surface
to provide a relatively wide gap at the lower edge of the blade
thereby permitting liquid to pass readily therethrough, and a
narrower gap at an upper end of the opening having substantially no
width thereby limiting passage of ambient air through the
opening.
In another aspect, the invention includes a squeegee assembly for
use with a mobile surface scrubber as previously described. The
squeegee assembly comprises leading and trailing elongate squeegee
blades of flexible material. Each blade has a lower edge engageable
with the surface to collect liquid on the surface for removal by
the vacuum system. In addition, the squeegee assembly includes a
mount for mounting the leading and trailing squeegee blades to the
scrubber frame in spaced apart relation to define a chamber
therebetween for accumulating liquid collected by the squeegee
blades. The chamber communicates with the vacuum system for
removing accumulated liquid from the chamber. The leading blade
includes a series of openings substantially as described above. The
relatively wide gap at the lower edge of the leading blade permits
liquid to pass readily therethrough into the chamber. The narrower
gap at an upper end of the opening limits passage of ambient air
into the chamber.
In yet another aspect, the present invention includes a mobile
surface scrubber for cleaning a surface with liquid. The scrubber
comprises a mobile frame, a cleaning solution dispensing system
mounted on the frame for wetting the surface with liquid and at
least one scrub brush attached to the frame for scrubbing the
surface when wetted with liquid. The scrubber also includes a
vacuum system connected to the frame for removing liquid from the
surface. Further, the scrubber includes leading and trailing
squeegee blades substantially as described above.
Other objects and features of the present invention will be in part
apparent and in part pointed out hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevation of a mobile surface scrubber
incorporating a squeegee assembly of the present invention;
FIG. 2 is a top plan of the squeegee assembly of FIG. 1 shown in
relation to a scrubber which is partially shown in phantom;
FIG. 3 is a cross section of the squeegee assembly taken in the
plane of line 3--3 of FIG. 2;
FIG. 4 is a side elevation of the squeegee assembly;
FIG. 5 is a cross section of the squeegee assembly taken in the
plane of line 5--5 of FIG. 4;
FIG. 6 is a rear elevation of the squeegee assembly in partial
section; and
FIG. 7 is a front elevation of a squeegee of the present
invention.
Corresponding reference characters indicate corresponding parts
throughout the several views of the drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, FIG. 1 illustrates a mobile surface
scrubber, indicated generally at 20, of the type used to sweep,
scrub and/or squeegee a surface such as a warehouse or factory
floor or a parking lot. The scrubber 20 has a frame 22 supporting a
body 24 which houses various scrubber components. A seat 26 mounted
on the body 24 permits an operator to ride on the scrubber 20. Hand
operated controls 28 and foot operated controls, generally
indicated at 30, are positioned in front of the seat 24 so the
operator may access them when seated to control the scrubber 20
operation. Two front wheels 32 (only one of which is visible in
FIG. 1) and one rear wheel 34 are mounted on the frame 22. The rear
wheel 34 is driven by an motor 36 (FIG. 2) to propel the scrubber
over the surface. The rear wheel 34 is pivotable about a vertical
axis so the scrubber 20 may be turned to travel to the left or
right.
The scrubber 20 is equipped with a sweeper system, generally
indicated at 40 in FIG. 2, which includes sweeper brushes or brooms
42, 44 and a vacuum (not shown) for removing loose debris. The
forward broom 42 is a rotary disk, curb broom which is rotatably
mounted on the frame 22 at its front right corner. The curb broom
42 rotates counterclockwise (as viewed from the top) about a
vertical axis to sweep debris toward the central longitudinal axis
or centerline 46 (FIG. 2) of the scrubber 20. As its name implies,
the curb broom 42 is particularly useful for sweeping debris away
from curbs, walls and other fixed obstructions. The rearward broom
44 is a rotary cylindrical, main broom positioned behind the front
wheels 32. The broom 44 rotates counterclockwise (as viewed in FIG.
1) about an horizontal axis to sweep debris forward and upward into
a collection bin (not shown) mounted on the frame 22 above and in
front of the front wheels 32. A vacuum filtration system (not
shown) retains the debris in the bin and prevents dust from
escaping into the surrounding environment. The previously described
aspects of the scrubber 20 and sweeper system 40 are conventional
and will not be described in further detail.
As further illustrated in FIG. 2, the scrubber system, indicated
generally at 50, comprises a cleaning solution dispensing system
52, a scrub brush assembly (generally designated by 54), and a
solution recovery system (generally designated by 56). As is
conventional in the art, the solution dispensing system 52 includes
a solution storage tank (not shown) and nozzles (not shown)
connected to the tank for dispensing cleaning solution from the
tank to the surface in the vicinity of the scrub brush assembly
54.
The scrub brush assembly 54 includes a chevron-shaped deck 60
secured to the frame 22, and three rotary disk scrub brushes 62
rotatably mounted on the deck. Each of the brushes 62 bears down on
the surface and rotates about a vertical axis to scrub the surface
when wetted with cleaning solution. The deck 60 is connected to the
frame 22 by two links 64 which are pivotally connected to both the
frame and the deck. An hydraulic actuator 66 connected between the
frame 22 and deck 60 permits the deck to be raised and lowered.
Side squeegees 70 are mounted outboard from the scrub brush
assembly 54. Each side squeegee 70 includes a blade 72 which wipes
the surface to keep the dispensed cleaning solution between the
side squeegees and beneath the scrubber 20. The side squeegees 70
are mounted on the frame 22 so they do not pivot substantially with
respect to the scrubber 20 as it turns left or right. However, each
side squeegee 70 includes a horizontal axle 80 connected to the
frame 22 so the squeegee
can pivot upward away from the surface to ride over obstacles and
follow the contour of the surface being scrubbed. Each side
squeegee 70 also includes an arm 82 which engages a bar 84
extending from the corresponding link 64 supporting the scrub brush
assembly 54 so the side squeegees raise when the scrub brush
assembly is lifted by the hydraulic cylinder 66.
The solution recovery system 56 includes a pivotally-mounted,
arcuate, rear squeegee assembly, generally designated by 90, for
collecting liquid such as used cleaning solution and a vacuum
system, generally designated by 92 (partially shown in FIG. 1) for
removing the collected liquid from the surface.
Referring to FIGS. 2, 3 and 5, the squeegee assembly 90 includes an
arcuate blade support, generally designated 100, having a
horizontal top 102 and a vertical wall 104 extending down from a
forward edge of the top and generally transversely with respect to
the scrubber centerline 46. Leading and trailing blades 106, 108,
respectively, are mounted behind the wall 104 of the blade support
100 for collecting liquid as will be explained in further detail
below. As shown in FIG. 5, tapered arcuate spacers 110 are
positioned between the leading and trailing blades 106, 108 to
space the blades and thereby form a chamber 112 (FIG. 3) between
the blades for accumulating liquid collected by the squeegee. An
adjustable arcuate clamp 114 hooks around the ends of the vertical
wall 104 of the blade support 100 to hold the blades 106, 108 and
the spacers 110 tightly in place in the squeegee assembly 90. Screw
fasteners 116 provided near opposite ends of the clamp 114 permit
the length of the clamp to be adjusted to vary how tightly the
clamp holds the blades 106, 108 and spacers 110 in place. As will
be understood by those skilled in the art, the clamp 114 attaches
the blades 106, 108 to the blade support 100 so they bend or flex
to conform to the surface being wiped.
The squeegee blades of the preferred embodiment are made of
flexible materials. Although the squeegee blades may be made of
other materials without departing from the scope of the present
invention, the leading blade 106 of the preferred embodiment is
made of urethane having a Shore A durometer hardness of between
about 75 and about 95 and the trailing blade 108 of the preferred
embodiment is made of gum rubber having a Shore A durometer
hardness of between about 35 and about 45. Further, although the
blades may have other dimensions without departing from the scope
of the preferred embodiment, the leading blade 106 is approximately
3.25 inches tall, approximately 0.13 inches thick and approximately
70.0 inches long and the trailing blade 108 is approximately 3.31
inches tall, approximately 0.25 inches thick and approximately
72.88 inches long.
As shown in FIG. 7, the leading blade 106 has a series of slits 120
through the blade extending up from its lower edge 122 at intervals
along the blade for permitting liquid to pass the leading blade and
accumulate in the chamber 112. The trailing blade 108 does not have
slits. Although the slits 120 in the leading blade 106 may have
other lengths without departing from the scope of the present
invention, the slits of the preferred embodiment are between about
0.7 and about 0.9 inches long. Although fewer or more slits may be
used without departing from the scope of the present invention, the
leading blade 106 of the preferred embodiment has 21 slits spaced
at about three inch intervals along the blade. Moreover, as shown
in FIG. 7, slits 120 are provided in the leading blade 106 along
its upper edge 124 as well as its lower edge 122 so the blade can
be inverted for continued use after the lower edge becomes
worn.
As illustrated in FIG. 6, the slits 120 in the leading blade 106
form tapered openings 126 when the lower edge 122 of the blade
engages the surface S and deflect as the scrubber moves along the
surface. The openings 126 have a relatively wide gap 128 at the
lower edge 122 of the blade 106 which permits liquid to pass
readily through the blade into the chamber 112. Each opening 126
has a narrow gap 130 at its upper end 132 to limit passage of
ambient air into the chamber 112. Although the openings may have
other configurations without departing from the scope of the
present invention, each generally V-shaped opening 126 of the
preferred embodiment tapers substantially uniformly from the lower
edge 122 of the blade 106 up to the upper end 132 of the opening.
Further, in the most preferred embodiment, the narrow gaps 130 at
the upper end 132 of the openings 126 have substantially no width
because the slits 120 are formed by cuts in the blade 106 having
kerfs of substantially no width. Thus, liquid collected by the
squeegee assembly 90 passes readily through the leading blade 106
into the chamber 112, but ambient air flow into the chamber is
restricted. Although the leading and trailing blades 106, 108,
respectively, of the preferred embodiment are continuous and one
piece, it is envisioned that they may be divided into two or more
lengths in an alternate embodiment.
As illustrated in FIGS. 2 and 4, a mount, generally designated 140,
is pivotally connected to the scrubber frame 22 for mounting the
squeegee assembly 90 on the scrubber 20. The mount 140 comprises a
connector plate 142 which engages the squeegee assembly 90 when
connecting the assembly to the mount. As shown in FIG. 6, bolts 144
extend up through the arcuate spacers 110 in the squeegee assembly
90 for fastening the assembly to the mount 140. Large nuts 146
threaded on the bolts 144 releasably fasten the squeegee assembly
90 to the connector plate 142. These nuts 146 may be manually
turned to remove and replace the squeegee assembly 90 without tools
when the blades 106, 108 are worn or the squeegee needs other
maintenance.
As further illustrated in FIGS. 2 and 4, a bracket 148 extends up
from the connector plate 142. This bracket 148 is pivotally
connected to two pairs of parallel links 150 which are pivotally
connected to the scrubber frame 22. The links 150 pivot about
vertical and horizontal axes with respect to the frame 22 and the
plate 142 to permit the rear squeegee 90 to rise and fall to ride
over obstructions. However, because the two links 150 of each pair
are parallel, the squeegee assembly 90 remains generally parallel
to the frame 22 as it rises and falls so the squeegee blades 106,
108 ideally contact the surface over their entire respective
lengths. Further, the links 150 permit the squeegee assembly 90 to
move from side to side with respect to the frame 22. Since the
forward ends of the pairs of links 150 are more closely spaced than
the rearward ends, the linkage forces the squeegee assembly 90 to
turn as it moves from side to side so the concave side of the
squeegee assembly is always directed toward the scrub brushes
62.
As illustrated in FIG. 2, a chain 152 connects the squeegee
assembly 90 to a pivotable lever 154 mounted on the frame 22. An
actuator 156 is mounted on the frame 22 for pivoting the lever 154
to raise and lower the squeegee assembly 90 as needed. The
flexibility of the chain 152 also permits the squeegee assembly 90
to rise and fall to pass over obstructions and to swing from side
to side during turns. Three casters 160 mounted along the squeegee
assembly 90 support the assembly so the blades 106, 108 wipe
against the surface S being cleaned. A roller 162 is mounted on
each end of the squeegee assembly 90 for rotation about a vertical
axis for fending the assembly off walls and other obstructions to
prevent damage to the assembly and the obstructions.
As shown in FIGS. 5 and 6, a generally rectangular tube 170
positioned between the arcuate spacers 110 generally at the center
of the squeegee assembly 90 provides a passage through the assembly
for providing communication between the chamber 112 and the vacuum
system 92. The tube 170 has a flange 172 extending from each side
(FIG. 6) for connecting the tube to the squeegee assembly 90 using
the bolts 144. An opening 174 in the connector plate 142 of the
mount 140 provides a passage through the mount, and a short
connecting sleeve 176 extending up from the connector plate 142
above the opening 174 connects the chamber 112 to a vacuum hose 178
of the vacuum system 92 as shown in FIG. 4. Thus, the chamber 112
communicates with the vacuum system 92 for removing accumulated
liquid from the chamber.
The previously described squeegee assembly 90 and vacuum system 92
form the solution recovery system 56 which collects and removes
virtually all of the liquid from the surface S. In fact, the
previously described recovery system has been found to remove
between about 95 and about 98 percent of the liquid from the
surface. Further, because the openings 126 restrict the amount of
ambient air entering the chamber 112, the flow rate requirement of
the vacuum system 92 is significantly reduced. For example, the
vacuum system 92 of the preferred embodiment is capable of removing
fluid (i.e., air and solution) from the chamber 112 at a rate of
about 150 cubic feet per minute. When prior art squeegees having
wide slots rather than the tapered slits were used, a vacuum system
capable of removing fluid at a rate of about 400 cubic feet per
minute was needed because significantly more air entered the
chamber 112. Further, a 1.5 horsepower motor drives the vacuum
system 92 of the preferred embodiment. When the prior art slotted
squeegees were used, a five horsepower motor was required.
In view of the above, it will be seen that the several objects of
the invention are achieved and other advantageous results
attained.
As various changes could be made in the above constructions without
departing from the scope of the invention, it is intended that all
matter contained in the above description or shown in the
accompanying drawings shall be interpreted as illustrative and not
in a limiting sense.
* * * * *